1. Field of the Invention
The present invention relates to a cassette for light-sensitive photographic material, and more particularly to a cassette for such material (which may be present in the cassette in form of a roll) which is to be transferred to a copying apparatus after the cassette has been connected to the same.
2. The Prior Art
It is known from the field of photographic copying or duplicating to provide cassettes which are loaded in a darkroom with light-sensitive photographic material (e.g. copy paper) and which are then removed from the darkroom to be connected to a copying apparatus outside the darkroom, e.g. a copying apparatus which is located in daylight. Since the access of light to the photographic material would spoil this material, such cassettes are connected to the copying apparatus in such a manner that no light can enter them and thereupon the photographic material is then transferred from the cassette into the copying apparatus for making copies in the same.
From German Pat. No. 762,768 a cassette is known having an outlet opening through which the light-sensitive photographic material issues to enter into a copying apparatus with which the cassette is light-tightly connected. Since, as is self-evident, the photographic material in the cassette must also be protected against the entry of light during its transfer from the darkroom (where the cassette has been loaded) to the copying apparatus to which it is to be connected, such cassettes must be provided with a sealing arrangement which prevents the entry of light into their interior. In the cassette according to the aforementioned German patent a set of rollers is provided adjacent the outlet of the photographic material. These rollers move into light-sealing engagement with one another while the cassette is not connected to the copying apparatus, and subsequent to its connection to such an apparatus they can be moved apart from one another (to permit free passage of the photographic material between them) by means of an electromagnetic arrangement that is provided for this purpose. This prior-art proposal does in fact provide a satisfactory seal for the cassette to prevent spoiling of the photographic material within the cassette by the entry of unwanted light. However, the arrangement needed to achieve this effect, including the electromagnetic device and the associated components, is rather expensive to produce and is also susceptible to malfunctions because it is comparatively complicated.